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V 


Issued  July  27,  1917. 

HAWAII  AGRICULTURAL  EXPERIMENT  STATION, 

J.   M.  WESTGATE,  Agronomist  in  Charge. 


Bulletin  No.  44. 


THE  LITCHI  IN  HAWAII. 


BY 


J.  E.  HIGGINS 

Horticulturist. 


UNDER   THE    SUPERVISION    OP 

STATES  RELATIONS  SERVICE, 
Office  of  Experiment  Stations, 

U.    S.    DEPARTMENT    OF   AGRICULTURE. 


\* 


^^JWMfiSMENT   PRINTING  OFFICE. 


1917 


Issued  July  27,  1917. 

HAWAII  AGRICULTURAL  EXPERIMENT  STATION, 

J.   M.  WESTGATE,  Agronomist  in  Charge. 


Bulletin  No.  44. 


THE  LITCHI  IN  HAWAII. 


BY 

J.  E.  HIGGINS, 

Horticulturist. 


UNDER  THE    SUPERVISION    OP 

STATES  RELATIONS  SERVICE, 

Office  of  Experiment  Stations, 

U.   S.   DEPARTMENT   OP  AGRICULTURE. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1917 


HAWAII  AGRICULTURAL  EXPERIMENT  STATION",  HONOLULU. 

(Under  the  supervision  of  A.  C.  True,  Director  of  the  States  Relations  Service,  United  States  Depart- 
ment of  Agriculture.] 

E.  W.  Allen,  Chief  of  Office  of  Experiment  Stations. 

Walter  H.  Evans,  Chief  of  Division  of  Insular  Stations,  Office  of  Experiment  Stations. 

STATION  STAFF. 

J.  M.  Westgate,  Agronomist  in  Charge. 

J.  Edgar  Higgins,  Horticulturist. 

M.  0.  Johnson,  Chemist. 

F.  G.  Krauss,  Superintendent  of  Extension  Work. 

C.  W.  Carpenter,  Plant  Pathologist. 

J.  B.  Thompson,  Assistant  Agronomist,  in  Charge  of  Glenwood  Substation. 

Alice  R.  Thompson,  Assistant  Chemist. 

C.  A.  Sahr,  Assistant  Agronomist. 

A.  T.  Longley,  In  Charge  of  Cooperative  Marketing  Investigations. 

J.'W.  Love,  Executive  Assistant. 


LETTER  OF  TRANSMITTAL 


Honolulu,  Hawaii,  October  30,  1916. 
Sir:  I  have  the  honor  to  submit  herewith  and  to  recommend  for  publication  as 
Bulletin  No.  44  of  the  Hawaii  Agricultural  Experiment  Station  a  paper  entitled 
"The  Litchi  in  Hawaii, "  by  J.  E.  Higgins,  horticulturist  of  this  station.  The  peculiar 
requirements  of  the  litchi  probably  are  responsible  for  its  tardy  utilization  both  in 
the  Hawaiian  Islands  and  the  citrus  belt  of  the  mainland  portion  of  the  United  States. 
Its  exquisite  flavor  has  made  it  a  favorite  fruit  in  the  Orient  for  thousands  of  years, 
and  it  is  expected  that,  with  a  proper  understanding  of  the  requirements  of  the  litchi 
as  regards  propagation  and  culture,  its  extensive  cultivation  in  the  warmer  portions 
of  the  United  States  will  be  attended  with  success. 
Respectfully, 

J.  M.  Westgate, 

Agronomist  in  Charge. 
Dr.  A.  C.  True, 

Director  States  Relations  Service, 

U.  S.  Department  of  Agriculture,  Washington,  D.  C. 

Publication  recommended. 
A.  C.  Tru.  ,  Director. 

Publication  authorized. 

D.  F.  Houston,  Secretary  of  Agriculture. 

(2) 


THE  LITCHI  IN  HAWAII.1 


CONTENTS. 


Page. 

Introduction 3 

Common  names  of  the  fruit 4 

History  and  distribution 4 

Natural  requirements 6 

Cultural  requirements 6 


The  litchi  crop 12 

The  litchi  as  food 13 

Insects  and  mites 15 

Varieties 18 

Botanical  status  and  relationships 20 


INTRODUCTION. 

Many  tropical  fruits,  hitherto  unknown  or  neglected  outside  their 
native  countries,  are  now  receiving  attention,  not  only  in  the  markets 
of  the  Temperate  Zone,  but  among  growers  in  the  Tropics  and  in 
subtropical  regions,  where  some  of  the  more  hardy  of  these  fruits 
are  being  acclimatized.  Within  a  generation  the  banana  has  passed 
from  a  rare  luxury  to  a  staple  food  product,  the  pineapple  from  a 
little  known  fruit  used  for  flavoring  to  a  highly  prized  article  of  food, 
sold  by  the  millions  of  cases  of  canned  as  well  as  fresh  fruit.  These 
two  fruits  are  but  the  pioneers,  and  others  are  following  close  after 
them  to  popularity.  The  grapefruit  has  already  established  itself. 
The  avocado,  the  most  conspicuous  aspirant  for  popular  favor  at 
the  present  time,  has  overcome  much  skepticism  and  now  appears  in 
varieties  that  can  be  grown  just  outside  the  Tropics,  hundreds  of 
acres  being  planted  in  Florida  and  California,  and  it  is  prevented 
from  becoming  the  basis  of  an  important  industry  in  Hawaii  only  by 
occasional  attacks  of  the  Mediterranean  fruit  fly,  which  place  this 
fruit  on  the  quarantine  list  in  the  Pacific  ports  of  the  United  States 
and  Canada. 

The  litchi,  the  subject  of  this  bulletin,  is  another  of  these  tropical 
or  subtropical  fruits  which  is  just  beginning  to  attract  commercial 
attention  outside  of  China,  its  native  country,  where  it  has  been 
cultivated  for  centuries.  To  the  people  who  have  lived  upon  the 
shores  of  the  Pacific  the  litchi  "nut"  is  a  more  or  less  famihar  article 
of  food,  especially  at  the  season  of  the  Chinese  New  Year.  Few  of 
those  who  dwell  east  of  the  Philippines,  however,  have  seen  the  fresh 
fruits  which,  when  dried,  form  the  litchi  nuts  of  commerce.  In 
most  varieties  the  ripe  fruit  has  an  outer  shell-like  covering  of  brilliant 
red,  giving  a  dish  of  them  a  striking  resemblance  to  large  straw- 
berries.    The  flesh  within  this  tough  outer  covering  is  white  with 

1  Litchi  chinensis  (Nephelium  litchi),  natural  order  Sapinlacese.    For  further  discussion  of  the  botanical 
status  and  relationships  see  p .  20. 

(3) 


about  the  consistency  of  a  Muscat  grape.  Its  delicious  flavor  makes 
the  litchi  highly  prized  by  those  who  are  familiar  with  it.  In  Hono- 
lulu the  limited  crop  is  retailed  at  prices  ranging  from  50  to  75  cents 
per  pound  (PL  I,  fig.  2).  Borne  in  clusters  (PL  II)  on  medium- 
sized  trees  with  dark-green  foliage,  these  fruits  usually  mature  about 
May  or  June  in  Hawaii.  Like  the  banana  and  pineapple,  the  litchi 
is  practically  immune  to  the  attacks  of  the  Mediterranean  fruit  fly, 
and  as  it  stands  shipment  well,  it  is  peculiarly  a  commercial  fruit. 
Because  of  the  desirability  of  increasing  greatly  the  cultivation 
of  the  litchi  in  Hawaii  and  because  of  the  newly  awakened  interest 
in  its  cultivation  elsewhere,  certain  experiments  have  been  con- 
ducted at  the  Hawaii  Agricultural  Experiment  Station  which, 
together  with  valuable  data  gathered  from  growers  here  and  abroad, 
are  reported  in  this  bulletin. 

COMMON  NAMES  OF  THE  FRUIT. 

The  name  of  the  fruit  appears  in  many  forms  as  " litchi/'  " lichee," 
"li tehee,"  "li  chee,"  "leechee,"  etc.  Most  of  these  are  presumably 
attempts  at  a  form  which  represents  the  sound  of  the  Chinese  name, 
but  none  of  them  quite  appears  to  have  succeeded.  The  sound,  as 
nearly  as  it  may  be  represented  in  the  English  language,  may  be 
indicated  by  "ly-chee,".with  about  equal  stress  on  each  part  of  the 
word.  But  since  the  form  " litchi"  is  fixed  definitely  as  a  part  of 
the  botanical  name  of  the  tree  (see  p.  3),  since  it  accurately  repre- 
sents the  sound  if  the  first  "i"  be  marked  long  and  the  second  short, 
and  since  this  form  probably  is  used  as  frequently  as  any  other,  it 
seems  desirable  that  it  should  be  adopted  as  the  common  name  and 
that  the  others  should  be  discarded. 

HISTORY  AND  DISTRIBUTION. 

References  to  the  litchi  occur  in  Chinese  writings  produced  long 
before  the  beginning  of  the  Christian  era.  Though  it  seems  im- 
possible to  determine  when  this  fruit  was  first  brought  under  cultiva- 
tion, it  is  very  generally  admitted  that  it  is  native  to  south  China. 
De  Candolle  states  that  "it  does  not  seem  that  any  botanist  has 
found  it  in  a  truly  wild  state,"1  and  suggests  that  this  may  be  due  to 
the  fact  that  the  southern  part  of  China  toward  Siam  has  been  little 
visited  by  botanists.  Long  since  introduced  into  India,  Ceylon,  and 
other  parts  of  the  Orient,  the  litchi  now  extends  to  southern  Japan, 
Formosa,  Australia,  and  Mauritius.  In  comparatively  recent  years, 
it  has  found  its  way  into  the  Western  Hemisphere  and  is  grown  in 
Brazil  and  in  some  of  the  West  Indies,  though  in  the  latter  region 
it  is  rare. 

i  Origin  of  Cultivated  Plants,  London,  1884,  p.  315. 


Bui.  44,  Hawaii  Agr.  Expt.  Station. 


Plate  I. 


Fig.  1.— A  Well-Grown  Litchi  Tree.    This  is  the  First  Litchi  Tree  Introduced 
into  the  Hawaiian  Islands. 


Fig.  2. 


-A  Basket  of  Litchi  Fruits  Sold  in  Honolulu  for  $25 
at  Current  Market  Prices. 


Bui.  44,  Hawaii  Agr.  Expt.  Station. 


Plate  II. 


A  Cluster  of  Litchi  Fruits,  Showing  the  Manner  in  Which  They  Are  Borne 

on  the  Trees. 


Mr.  Ching  Shai,  of  Honolulu,  is  authority  for  the  statement  that 
the  first  litchi  tree  was  brought  to  Hawaii  about  the  year  1873  by 
Mr.  Ching  Check.  The  tree  was  planted  on  the  property  of  Mr.  C. 
Afong  and  is  now  the  best  known  of  the  litchi  trees  in  Honolulu 
(PL  I,  fig.  1).  Usually  it  has  borne  fruit  abundantly,  and  the  crop  of 
this  single  tree  is  said  to  have  sold  at  prices  ranging  from  $75  upward 
in  ordinary  years,  so  rare  and  so  highly  prized  is  this  fruit.  Other 
introductions  have  been  made  by  the  United  States  Department  of 
Agriculture  and  by  Messrs.  Sing  Chong,  Wong  Kwai,  Wong  Leong, 
Luke  Chan,  E.  W.  Jordan,  and  others.  In  transit  and  immediately 
after  arrival  the  rate  of  mortality  among  the  plants  usually  has  been 
extremely  high,  so  that  comparatively  few  trees  have  become  estab- 
lished. In  one  instance  where  400  trees  were  imported,  only  four 
are  said  to  have  survived.  These  losses  have  been  due  in  part  to  the 
shipment  of  plants  without  an  established  root  system  and  in  part 
to  the  long  voyage,  followed  by  the  treatment  necessary  to  prevent 
the  introduction  of  dangerous  insects  and  diseases.  In  order  to 
introduce  and  establish  the  choicest  varieties  it  will  be  necessary  to 
make  special  arrangements  to  insure  their  safe  arrival.  It  is  probably 
because  of  the  difficulty  of  transporting  the  plants,  the  impossibility 
of  shipping  the  seed  under  ordinary  conditions,  the  slowness  of  the 
present  cumbersome  methods  of  propagation,  and  the  extreme 
tardiness  of  many  seedlings  in  coming  into  bearing  that  the  litchi  is 
represented  by  only  a  few  trees  in  countries  where  the  soil  and  climatic 
conditions  favor  its  extensive  production. 

The  litchi  is  believed  to  have  been  introduced  into  Florida  about 
1886  or  1887.  Since  that  date  several  introductions  have  been  made 
by  the  United  States  Department  of  Agriculture  and  by  private 
nurserymen.  Very  many  of  these  trees  died  before  they  became 
established.  Of  the  few  that  now  remain  some  are  said  to  promise 
success.  In  a  letter  to  this  station  under  date  of  August  29,  1916, 
Mr.  W.  S.  Taylor,  of  Tampa,  Fla.,  stated  that  litchi  trees  sent  him 
by  the  Office  of  Foreign  Seed  and  Plant  Introduction,  of  the  Depart- 
ment of  Agriculture,  fruited  in  July.  Mr.  Taylor,  who  is  familiar 
with  the  litchi  in  China,  reports  that  the  Florida  fruit  was  "excep- 
tionally large  and  fine."  Although  it  has  taken  many  years  to 
demonstrate  the  possibility  of  the  litchi's  fruiting  in  Florida,  an 
ardent  hope  is  now  revived  that  with  suitable  varieties  the  litchi  may 
become  the  basis  of  an  industry.1 

The  first  litchi  tree  to  be  introduced  into  California  is  said  to  have 
come  from  Florida  and  was  planted  by  Mr.  E.  W.  Hadley  in  Santa 
Barbara  about  1897.  This  tree  was  obtained  as  a  small  plant  from 
Reasoner  Bros.,  Oneca,  Fla.2     Mr.  E.  N.  Reasoner  states  that  this 

i  The  recent  freeze  in  Florida,  when,  on  Feb.  3, 1917,  the  temperature  went  to  2<'<°  P.,  killed  six-year 
ol'l  trees  to  the  ground,  but  they  appear  to  be  sprouting  up  again.— D.  G.  Fairc-hild. 

1  Letter  to  Mr.  Peter  Bisset,.Oflice  of  Foreign  Seed  and  Plant  Introduction,  United  Stales  Department 
of  Agriculture,  dated  Jan.  14,  1916. 


California  tree  was  originally  imported  from  Saharanpur,  India.  It 
first  fruited  in  1913.  It  is  possible  that  varieties  from  the  hill  coun- 
try of  India  may  prove  best  adapted  to  California  and  Florida  condi- 
tions. The  United  States  Department  of  Agriculture  has  placed  a 
number  of  litchi.  trees  in  different  parts  of  California,  and  the  writer 
distributed  a  considerable  number  of  seeds  in  that  State  in  July,  1914. 

NATURAL  REQUIREMENTS. 

The  litchi  appears  to  belong  just  within  or  near  the  border  of  the 
Tropics.  When  the  tree  is  young  it  is  very  sensitive  to  frost,  but 
when  mature  it  is  reported  that  considerable  cold  is  endured  without 
injury.  Mr.  A.  C.  Hartless,  superintendent  Government  Botanical 
Gardens,  Saharanpur,  India,  states,  in  a  letter  to  the  writer,  that  the 
trees  "have  been  known  to  stand  11°  of  frost."  In  south  China  the 
litchi  is  grown  on  comparatively  low  lands,  but  nearer  the  Equator  in 
India  its  cultivation  is  extended  to  considerable  elevations.  Definite 
data  are  not  available  as  to  the  optimum  atmospheric  moisture,  but 
the  evidence  indicates  that  a  rather  high  humidity  is  desirable. 
Abundant  rainfall  is  important  unless  irrigation  is  applied,  but  heavy 
rains  during  the  flowering  season  are  injurious.  It  is  believed  in 
China  that  electrical  storms  interfere  with  the  production  of  flowers 
and  fruit.  Whether  this  be  well  founded  or  not,  it  may  be  worth 
while  to  record  that  the  1916  crop  in  Honolulu  was  a  total  failure  and 
that  the  few  months  preceding  the  flowering  season  witnessed  some  of 
the  most  severe  electrical  storms  that  have  occurred  in  the  city  in 
many  years. 

A  deep,  moist,  alluvial  soil  seems  best  adapted  to  the  needs  of  the 
litchi,  but  it  prospers  in  a  rather  heavy  and  compact  soil.  In  China, 
a  favorite  place  for  planting  is  along  the  banks  of  streams  or  on  the 
dikes  between  rice  fields.  Though  the  litchi  has  been  grown  chiefly 
in  very  heavy  soils  in  Hawaii,  in  the  absence  of  exhaustive  experi- 
ments it  is  impossible  to  state  positively  that  it  would  not  do  equally 
well  in  light  soils,  provided  the  moisture  requirements  were  well 
maintained. 

CULTURAL  REQUIREMENTS. 

Much  is  yet  to  be  learned  regarding  the  cultural  requirements  of 
this  tree.  No  orchard  experiments  with  the  litchi  are  on  record  in 
any  of  the  meager  and  fragmentary  literature  available  on  the 
subject.  Unless  there  is  a  liberal  rainfall  or  a  constant  subterranean 
supply  of  water,  abundant  irrigation  is  necessary.  It  is  well  known 
also  that  large  quantities  of  fertilizer  are  used  in  the  cultivation  of 
the  litchi.  It  is  the  custom  of  some  of  the  Chinese  growers  to  apply 
night  soil  several  times  during  the  year.  For  this  purpose  a  shallow 
trench,  dug  near  the  ends  of  the  roots  of  the  tree,  is  filled  with  the 
fertilizer  which  is  covered  with  soil.     Duck  manure  also  is  a  favorite 


fertilizer  with  the  growers  of  the  Orient.     Some  growers  prefer  to  put 

the  manure  on  as  a  top-dressing  and  cover  it  with  a  heavy  mulch 
because  of  the  tendency  of  the  litchi  to  form  surface  roots.  No 
experiments  with  chemical  fertilizers  have  been  reported. 

Considerable  difference  of  opinion  appears  to  exist  with  regard  to 
pruning,  some  growers  stating  that  no  pruning  should  be  practiced, 
others  insisting  that  the  breaking  off  of  the  ends  of  old  branches  is 
beneficial.  The  customary  maimer  of  gathering  the  fruit,  by  break- 
ing with  it  branches  10  to  12  inches  long,  provides  in  itself  a  form  of 
pruning  which  some  growers  insist  is  necessary  for  the  continued 
productivity  of  the  tree,  but  here  also  there  is  much  need  for  more 
exact  data. 

The  trees  should  be  planted  at  least  30  feet  apart,  and  under  good 
conditions  they  will  require  even  more  space  before  they  have 
attained  full  size.  Opinions  differ  as  to  the  value  of  shade,  but 
young  trees  in  a  country  of  clear  skies  doubtless  will  benefit  by  some 
protection  from  direct  sunlight.  It  is  important  that  the  plantings 
be  protected  from  heavy  winds  at  all  times,  but  particularly  during 
the  flowering  season.  For  this  purpose  a  sheltered  spot  should  be 
chosen  as  a  site  for  the  plantings,  or  windbreaks  should  be  provided 
in  a  region  where  strong  winds  prevail. 

PROPAGATION. 

SEEDS. 

The  litchi  reproduces  readily  by  seeds,  this  being  the  simplest 
method  of  reproduction,  since  most  of  the  varieties  of  this  fruit  pro- 
duce viable  seeds  which  germinate  quickly.  In  experiments  con- 
ducted at  this  station  it  has  been  found  that  some  seeds  will  begin 
to  germinate  within  three  days  after  planting. 

Preservation. — The  seeds  are  extremely  short  lived,  retaining  their 
viability  not  more  than  four  or  five  days  under  ordinary  conditions. 
Experiments  to  determine  the  longevity  of  these  seeds  under  different 
conditions  were  carried  on  during  the  summer  of  1915.  In  Honolulu 
in  June,  1915,  seeds  exposed  to  the  air  under  normal  humidity  con- 
ditions began  to  shrivel  in  less  than  24  hours,  and  the  percentage  of 
germination  fell  rapidly  as  the  period  of  exposure  was  prolonged 
two,  three,  four,  and  five  days.  After  the  fifth  day  practically  all 
seeds  were  dead.  In  dry  charcoal  or  similar  dry  material  the  loss  of 
moisture  and  consequent  loss  of  viability  proceeds  almost  as  rapidly 
as  in  the  air.     Seeds  so  kept  for  one  week  entirely  failed  to  germinate. 

It  therefore  appears  that  to  preserve  the  germinability  of  litchi 
seeds  it  is  necessary  to  prevent  in  some  way  the  loss  of  moisture.  In 
the  fruit  the  seed  is  protected  to  a  considerable  degree,  but  in  a  dry 
atmosphere  the  rapid  drying  of  the  aril  causes,  after  a  few  weeks,  a 
marked    loss    of    viability,    varying    with    atmospheric    conditions. 


8 

Fruit  spread  out  in  direct  sunlight  quickly  changes  to  litchi  "nuts," 
but  if  closely  packed  in  a  closed  room  remains  moist  a  fairly  long 
time. 

In  refrigeration  the  fruits  retain  their  freshness  much  longer,  and 
the  seeds  appear  uninjured,  although  no  data  are  at  hand  relating 
to  the  germinating  power  of  litchi  seeds  from  fruits  kept  at  low  tem- 
peratures for  periods  longer  than  two  weeks.  From  the  fact  that 
seeds  of  fruits  stored  for  two  weeks  at  about  38°  F.  gave  perfect  ger- 
mination, it  would  appear  that  seeds  may  be  kept  for  a  considerable 
period  by  this  method  without  injury.  No  tests  of  refrigeration  as  a 
means  of  preserving  seeds  separated  from  the  fruit  have  been  made 
in  Hawaii. 

Keeping  the  fruits  in  distilled  water  for  two  or  three  weeks  did  not 
appear  to  injure  the  seeds  seriously,  and  this  method  may  be  used 
to  preserve  the  seed  where  refrigeration  is  not  available. 

Moist  sphagnum  moss  appears  to  be  one  of  the  best  media  for  the 
preservation  of  the  seeds  in  transit.  In  experiments  at  his  station 
the  moss  was  first  saturated  with  water  and  then  wrung  by  hand 
in  a  piece  of  burlap  until  as  dry  as  possible.  So  treated  it  contained 
water  equal  to  212  per  cent  of  its  own  weight  when  air  dried.  A 
layer  of  this  moist  moss  about  an  inch  thick  was  spread  upon  a  sheet 
of  heavy  waxed  paper,  the  seeds  distributed  at  regular  intervals  upon 
it  and  covered  with  another  layer  of  moss  of  equal  thickness.  The 
package  was  then  rolled,  wrapped  with  a  layer  of  crimped  straw- 
board  or  corrugated  paper  to  prevent  breaking  the  waxed  paper,  and 
finally  covered  with  a  heavy  manilla  wrapper.  Thus  packed,  seeds 
were  shipped  by  mail  to  Florida,  many  packages  being  sent  in 
this  manner  and  all  reported  as  arriving  in  excellent  condition. 
Similar  packages  were  held  at  the  station  for  periods  varying 
from  two  to  eight  weeks.  After  being  kept  as  long  as  eight  weeks 
in  this  moist  medium  the  seeds  had  germinated  and  produced 
sprouts  so  large  as  to  require  extreme  care  in  handling  to  avoid 
injury.  However,  a  large  majority  of  the  plantlets  could  be  saved 
even  after  so  long  a  period,  which,  it  will  be  observed,  is  sufficient 
for  mail  shipment  to  almost  any  part  of  the  Tropics.  It  is  probable 
that  less  moisture  than  was  used  in  the  moss  in  the  experiments 
would  prevent  the  drying  out  of  the  seeds  and  would  retard  germina- 
tion. A  mixture  of  finely  cut  sphagnum  and  powdered  charcoal 
slightly  but  uniformly  moistened  and  placed  in  a  tin  tube  serves  the 
same  purpose. 

Sowing. — From  the  foregoing  facts  it  is  apparent  that  the  seeds 
ought  to  be  sown  at  the  earliest  possible  moment  after  they  are 
removed  from  the  fresh  fruits,  necessary  delays  even  of  one  day 
requiring  special  precautions  to  prevent  deterioration.  They  should 
be  sown  in  pots  sunk  in  well-drained  soil.     If  small  pots  are  used, 


precautions  must  he  taken  to  prevent  the  drying  out  of  the  soil  by 
evaporation  from  the  sides  of  the  pots.  This  may  he  done  by  placing 
the  pots  in  moistened  moss,  sawdust,  or  sand  from  which  any  salt 
which  may  have  been  present  has  been  washed.  The  seeds  should 
be  placed  horizontally  about  one-half  inch  beneath  the  surface  of 
the  soil,  and  the  young  seedlings  should  be  partially  shaded. 

LAYERING. 

As  seeds  do  not  reproduce  the  variety  from  which  they  have  been 
taken,  and  as  the  seedlings  are  of  rather  slow  growth  and  require 
many  years  to  come  into  bearing,  it  has  for  many  years  been  the 
custom  in  China,  the  land  of  the  litchi,  to  propagate  the  best  varieties 
by  layering  or  by  air-layering,  a  process  which  has  come  to  be  known 
as  "Chinese  layering"  and  is  applied  to  many  kinds  of  plants.  In 
air-layering,  a  branch  is  surrounded  with  soil  until  roots  have  formed, 
after  which  it  is  removed  and  established  as  a  new  tree.  In  applying 
the  method  to  the  litchi,  a  branch  from  three-fourths  inch  to  1J 
inches  in  diameter  is  wounded  by  the  complete  removal  of  a  ring 
of  bark  just  below  a  bud,  where  it  is  desired  to  have  the  roots  start. 
The  cut  usually  is  surrounded  by  soil  held  in  place  by  a  heavy  wrap- 
ping of  burlap  or  similar  material,  although  sometimes  a  box  is 
elevated  into  the  tree  for  this  purpose.  Several  ingenious  devices 
have  been  made  to  supply  the  soil  with  constant  moisture.  Some- 
times a  can  with  a  very  small  opening  in  the  bottom  is  suspended 
above  the  soil  and  filled  with  water  which  passes  out  drop  by  drop 
into  the  soil.  Again,  sometimes  the  water  is  conducted,  from  a  can 
or  other  vessel  placed  above  the  soil,  by  means  of  a  loosely  woven 
rope,  one  end  of  which  is  placed  in  the  water  the  other  on  the  soil, 
the  water  passing  over  by  capillarity. 

Air-layering  usually  is  commenced  at  about  the  beginning  of  the 
season  of  most  active  growth,  and  several  months  are  required  for 
the  establishment  of  a  root  system  sufficient  to  support  an  independent 
jtree.  When  a  good  ball  of  roots  has  fonried,  the  branch  is  cut  off 
below  the  soil,  or  the  box,  after  which  it  generally  is  placed  in  a  larger 
box  or  tub  to  become  more  firmly  established  before  being  set  out 
permanently.  At  first  it  is  well  to  provide  some  shade  and  protection 
from  the  wind,  and  often  it  is  necessary  to  cut  back  the  top  of  the 
branch  severely,  so  as  to  secure  a  proper  proportion  of  stem  to  root. 

Some  modifications  of  this  old-world  method  have  been  practiced 
with  success  at  this  station.  One  of  these  consists  in  using  a  long 
trough-shaped  box,  in  which  several  branches  may  be  rooted  at  the 
same  time,  thus  increasing  the  number  of  plants  which  may  be  propa- 
gated with  a  given  amount  of  labor  and  attention.  For  this  purpose, 
rather  small  branches  not  more  than  a  half-inch  in  diameter  are  laid 
across  the  trough  through  notches  cut  in  the  sides  of  the  box.     With 

8556.5—17 2 


10 

the  low  trees  used  here,  it  has  been  much  more  economical  to  apply 
the  water  by  hand  daily  than  to  prepare  the  contrivances  mentioned 
above  for  maintaining  the  moisture.  When  the  branches  have 
established  root  systems,  the  box  is  removed  from  the  tree  and  the 
soil  washed  out  carefully  with  a  stream  of  water.  This  process, 
without  injuring  the  roots,  permits  easy  separation  of  the  rooted 
stems  of  the  different  branches,  if  these  have  not  been  allowed  to 
remain  too  long  on  the  tree.  Plate  III,  figure  2,  shows  one  of  these 
troughs  with  rooted  branches  which  are  being  removed  to  be  estab- 
lished as  independent  plants. 

Another  modification  of  layering,  used  successfully  on  low  trees 
or  on  trees  which  can  be  surrounded  easily  by  a  platform,  consists 
in  the  use  of  small  branches,  not  more  than  a  quarter  of  an  inch  in 
diameter,  laid  through  one  side  of  a  gallon  tin  cut  for  the  purpose. 
These  make  small  plants,  but  many  more  can  be  taken  from  the 
tree  without  reducing  its  size  seriously.  It  is  too  early  to  state  how 
long  it  may  take  these  little  plants  to  catch  up  with  those  that  have 
been  started  from  larger  branches. 

Although  layering  has  the  advantage  of  exact  reproduction  of 
varieties  and  rapid  fruiting,  nevertheless,  it  is  a  slow  and  cumbersome 
method  not  well  adapted  to  the  rapid  multiplication  of  varieties 
usually  desired  by  American  nurserymen.  There  is  also  ground  for 
the  belief  that  its  excessive  use  may  have  a  devitalizing  effect  Upon 
the  parent  tree.  Girdling  for  the  purpose  of  forcing  heavy  production 
of  fruit  is  generally  believed  to  have  such  an  effect  upon  litchi  trees, 
perhaps  because  the  root  system  and  other  parts  of  the  parent  tree 
are  robbed  of  the  energy  used  in  forcing  fruit  production  in  the 
girdled  branches.  It  is  not  unreasonable  to  suppose  that  something 
of  the  same  effect  may  follow  the  production  of  new  root  systems  on 
many  branches.  While  no  definite  data  can  be  recorded,  there  is 
some  evidence  supporting  this  belief. 

BUDDING    AND    GRAFTING. 

With  the  exception  of  a  limited  use  of  inarching,  the  practice  of 
budding  or  grafting,  almost  universally  employed  in  the  commercial 
culture  of  fruit  trees  and  vines  in  America  and  Europe,  is  scarcely 
ever  applied  to  the  litchi.  A  number  of  trees  have  been  spoken  of 
in  a  general  way  as  budded  trees  of  the  litchi,  but  closer  investigation 
has  proved  them  to  have  been  layered.  Aside  from  the  advantages  of 
speed  and  facility  in  multiplication,  budding  and  grafting  afford  the 
opportunity  to  use,  as  root  stocks,  other  varieties  or  species,  which 
may  offer  as  decided  advantages  in  the  case  of  the  litchi  as  are  well 
known  to  exist  in  the  case  of  many  other  fruit  trees.  For  example, 
the  litchi  grows  slowly  and  frequently  requires  eight  or  nine  years  in 
Hawaii  to  come  into  bearing,  even  when  grown  from  layers.  Kelated 
species  which  are  of  more  rapid  growth,  are  known,  and  these  should 


11 

be  tested  as  stocks  for  the  litchi.  It  is  probable  also  that  stocks 
may  be  found  which  will  increase  the  hardiness  of  the  litchi  and  thus 
make  it  possible  to  cultivate  it  outside  of  the  Tropics.  Resistance 
to  disease  and  insect  attack  also  is  to  be  considered,  and  in  this  con- 
nection it  is  worth  while  to  mention  the  apparent  immunity  of  the 
longan  (Euphoria  Ion  go  no  or  Dimocarpus  longan)  to  the  attacks  of 
the  erinose  mite,1  which  is  destructive  to  the  foliage  of  the  litchi  if 
not  held  in  control.  While  the  Chinese  have  not  used  other  species 
for  stocks,  in  their  inarching  varietal  preferences  have  been  discovered. 
Mr.  G.  Weidman  Groff  states  that  the  variety  Loh  Mai  Chi  is  inarched 
generally  upon  the  variety  San  Chi  about  Canton.2 

Experiments  in  grafting  and  budding  the  litchi  on  the  longan  have 
received  some  attention  at  this  station.  A  method  of  bark  grafting 
has  proved  thus  far  successful  as  a  means  of  uniting  these  two  species, 
now  usually  classified  as  of  different  genera.  This  has  been  used  so 
far  only  in  top-working  the  longan  trees.  The  method  consists  in 
cutting  off  branches  from  1  to  2  inches  in  diameter  and  immediately 
inserting  in  these  small  scions  of  mature  wood  from  the  desired 
variety  of  litchi,  making  incisions  in  the  bark,  beginning  at  the  top 
of  the  cut  in  the  stump  and  running  down  3  or  4  inches.  This 
process  is  illustrated  in  Plate  III,  figure  1.  The  wound  is  smeared 
with  grafting  wax,  while  the  scion  and  top  of  the  stock  are  covered 
with  a  heavy  paraffined  paper  bag.  The  bag  is  tied  about  the  branch 
to  prevent  excessive  transpiration,  as  this  would  destroy  the  scion 
before  it  could  become  united  to  the  stock.  After  about  three  weeks 
this  may  be  removed,  as  it  has  been  found  that  the  scion  united  with 
the  stock  by  that  time. 

Repeated  experiments  with  this  method  have  shown  that  there  is 
no  great  difficulty  in  securing  a  union  of  the  litchi  with  the  longan 
(PI.  IV,  fig.  1).  A  noteworthy  influence  of  the  stock  on  the  scion 
should  be  mentioned  here.  The  growth  produced  is  very  much  more 
rapid  than  that  of  the  litchi  on  its  own  roots,  and  in  some  cases  the 
character  of  the  foliage  appears  to  undergo  a  change.  It  is,  of 
course,  too  early  in  these  experiments  to  know  anything  about  hardi- 
ness, resistance  to  disease,  kind  of  fruits,  or  many  other  important 
features.3 

The  budding  of  the  litchi  on  the  longan  has  been  accomplished  in 
Hawaii,  but  this  method  is  not  so  successful  as  that  of  grafting 
described  above. 

1  Vide,  \>.  17. 

*  U.  S.  Dept.  Agr.,  Bur.  Plant  Indus.,  Plant  Immigrants  No.  111-112  (1916),  p.  908. 

3  Since  the  above  was  written,  attention  has  been  called  to  repeated  failures  to  make  effective  and 
permanent  unions  between  these  two  genera  where  this  work  has  been  tried  :n  Washington,  D.  C,  and 
in  Florida.  Unions  are  reported  to  have  been  made  but  they  have  not  been  permanent.  This  is  not  an 
uncommon  result  when  grafting  is  attempted  between  widely  different  plants.  At  this  time  (Mar.  :*, 
1917),  the  Hawaii  Experiment  Station  plants  are  in  a  flourishing  conuition,  this  being  thirteen  months 
after  the  setting  of  the  scions.  None  has  been  lost  since  the  first  few  weeks,  when  two  failed.  It  is, 
however,  too  soon  to  know  whether  these  unions  will  be  permanent. 


12 


THE  IITCHI  CROP. 


The  litchi  ripens  fruit  at  different  times  in  various  countries,  May 
and  June  being  the  season  in  Hawaii,  while  July  is  midseason  in  China. 

The  bearing  age  of  the  litchi  is  extremely  variable,  particularly  if 
the  trees  are  grown  from  seed.  Seedlings  in  Hawaii  have  been  known 
to  fruit  in  five  years,  while  others  have  continued  to  grow  and  thrive 
for  over  20  years  without  producing  a  single  flower.  That  this  is  not 
always  due  to  cultural  and  natural  conditions  is  demonstrated  by 
three  layered  litchi  trees  and  one  seedling  growing  in  the  same  yard 
under  practically  identical  conditions,  the  layered  trees  having  borne 
regularly,  while  the  seedling  tree,  now  24  years  old  and  over  30  feet 
high,  has  never  produced  flowers.  Numerous  instances  of  this 
character  have  given  rise  to  the  general  statement  that  seedling  litchis 
do  not  come  into  bearing  until  they  are  20  or  more  years  old,  but  a 
number  of  cases  are  on  record  to  disprove  the  universality  of  this 
statement.  Wide  variability  in  the  age  of  coming  into  bearing  has 
been  noted  with  seedlings  of  other  tropical  fruits,  especially  the 
avocado,  but  the  litchi  appears  most  extreme  in  this  respect. 

Layered  trees,  if  rooted  from  large  branches,  frequently  flower  in 
one  year  in  China,  although  under  the  best  methods  of  cultivation 
the  first  year's  flowers  are  removed  to  prevent  exhaustion  by  fruit 
bearing,  a  proceeding  sometimes  followed  during  the  second  year. 
Under  Hawaiian  conditions,  however,  even  layered  trees  commonly 
do  not  bear  as  young  as  do  the  trees  in  China,  several  years  usually 
elapsing  before  any  fruit  is  produced.  The  fact  that  most  of  the 
trees  of  which  record  exists  in  Hawaii  have  been  planted  on  uplands 
may  cause  their  comparative  tardiness  in  coming  into  bearing.  This 
possibly  may  be  overcome  when  the  needs  of  the  tree  are  understood 
more  clearly  and  supplied  more  definitely. 

The  productivity  of  the  litchi  is  said  to  last  for  centuries  in  its 
native  home,  and  while  it  would  not  be  safe  to  depend  upon  such 
allegations,  it  is  a  well-established  fact  that  the  tree  continues  to 
produce  liberal  crops  of  fruit  through  many  years. 

From  the  limited  data  on  the  litchi  in  Hawaii,  the  yield  of  fruit  of  a 
good,  mature  tree  may  be  placed  at  200  to  300  pounds  per  season. 
Some  trees  are  reported  to  have  produced  about  1,000  pounds. 

As  has  been  stated,  in  picking  the  fruit  it  is  customary  to  break  off 
branches  10  to  12  inches  long  with  the  clusters,  which  are  taken  to 
market  in  this  condition  and  sold  by  weight,  including  the  branches 
and  leaves.  In  some  fruits,  bought  on  condition  that  no  branch 
exceed  5  inches  in  length  below  the  fruits,  it  was  found  that  the  sticks 
constituted  3  per  cent  of  the  total  weight.  In  an  analysis  of  this 
particular  lot  it  was  found  that  the  seeds  constituted  17.03,  the  skin, 
or  shell,  7.86,  and  the  flesh  75.1  per  cent  of  the  weight  of  the  fruit. 

The  fruits  of  the  litchi  very  quickly  lose  their  bright  color  and  with  it- 
their  attractive  appearance  in  the  market.     It  is  important  to  pre- 


Bui.  44,  Hawaii  Agr.  Expt.  Station. 


Plate  III. 


Fiq.  1.— Grafting  the  Litchi  on  the  Longan  by  the  Bark-Grafting  Method. 


Fig.  2.— A  Method  of  Air-Layering  the  Litchi. 


Bui.  44,  Hawaii  Agr.  Expt.  Station. 


Plate  IV. 


13 

serve  the  color  in  order  to  realize  the  full  value  of  the  fruit.  The 
Chinese  sometimes  sprinkle  the  fruits  with  a  weak  salt  solution  and 
pack  them  in  bamboo,  sealed  at  each  end  with  clay,  for  shipment  to 
distant  markets.1  In  experiments  at  this  station  it  was  found  possible 
to  keep  the  fruits  in  distilled  water  for  about  two  weeks  with  only 
slight  deterioration  in  appearance  and  flavor,  a  practice  sometimes 
followed  in  the  Orient.  Refrigeration,  where  it  is  available,  furnishes 
the  best  means  of  preserving  the  litchi  for  a  limited  period  in  its 
natural  state.  No  experiments  on  the  prolonged  use  of  refrigeration 
have  been  reported.  Fruits  shipped  in  refrigeration  from  this  station 
to  San  Francisco  and  thence  without  artificial  cooling  to  Washington, 
D.  C,  and  to  Florida,  are  reported  to  have  arrived  in  good  condition, 
'although  some  loss  in  color  must  have  occurred  after  the  fruits  were 
removed  from  refrigeration.  Refrigerated  fruits  under  observation  in 
transit  from  Honolulu  to  San  Francisco,  and  still  others  kept  in 
Honolulu,  showed  no  loss  in  color  or  flavor.  These  were  held  in 
refrigeration  about  two  weeks  before  examination.  There  is  no 
doubt  that  refrigeration  will  provide  a  very  satisfactory  method  for 
placing  upon  American  markets  the  litchi  crop  grown  in  Florida, 
California,  Hawaii,  Porto  Rico,  or  Cuba. 

Litchi  "nuts,"  which  are  simply  the  dried  fruits,  are  prepared  either 
by  sun  drying  or  by  artificial  heat,  the  smi-dried  "nuts"  usually 
commanding  the  higher  price.  The  drying  process  begins  very  soon 
after  the  fruits  are  exposed  to  free  ventilation  and  to  direct  sunlight. 
A  large  part  of  the  litchi  crop  of  China  is  marketed  in  the  dried  form 
and  finds  its  way  to  many  parts  of  the  world.  Considerable  quan- 
tities of  the  fruit  also  are  canned  in  sirup. 

THE  LITCHI  AS  FOOD. 
THE  FRESH  FRUIT. 

An  analysis  of  fresh  litchis,  made  in  June,  1915,  by  Miss  Alice  R. 

Thompson,    assistant   chemist    of   this   station,    gave   the   following 

results : 

Analysis  of  fresh  litchis. 

Per  cent. 

Edible  portion 51 

Waste  (seeds  and  shell) 49 

Total  solids 20. 92 

Insoluble  solids 1.  79 

Ash 541 

Acids  as  sulphuric  acid 16 

Protein 1. 15 

Reducing  sugars 12.  5 

Sucrose 2.8 

Total  sugars 15.  3 

Direct  polarization  at  29°  0.,  °V,  0.3. 
Invert  polarization  at  29°  C,  °V,  3.  2. 

s  U.  S.  Dept.  Agr.,  Bur.  Plant  Indus.,  Plant  Immigrants  No.  111-112  (1916).  p.  91G. 


14 

By  comparing  the  figures  of  this  analysis  with  those  given  on 
page  12  it  will  be  seen  that  the  waste  portion  here  is  much  greater. 
Although  neither  lot  of  fruit  had  small  seeds,  yet  the  size  of  those  in 
Miss  Thompson's  analysis  was  unusual,  which  accounts  for  the  large 
proportion  of  waste  in  the  total  weight.  The  analysis,  however, 
serves  to  show  the  excellent  composition  of  the  flesh  of  this  unusual 
fruit. 

A  taste  for  the  fresh  litchi  does  not  have  to  be  acquired,  as  Ifhe 
flavor  appeals  to  nearly  everyone.  Wherever  the  litchi  is  known  it 
is  prized  as  one  of  the  best  of  tropical  fruits.  The  pulp  is  meaty, 
much  like  that  of  a  white  Malaga  grape,  and  the  flavor  is  very 
pleasant.  The  raw  pulp,  freed  from  seed  and  shells,  makes  a  palat- 
able dish. 

THE  PRESERVED  FRUIT. 

A  number  of  experiments  were  conducted  at  this  station  by  Mrs. 
J.  M.  Westgate  on  various  ways  of  preparing  and  preserving  the 
litchi  for  food.  The  fruits  were  freed  from  seeds  and  shells  and 
11  pounds  and  5  ounces  of  the  pulp  used  in  cooking  experiments. 
The  preserving  was  done  in  June,  1915,  and  the  jars  opened  in 
October,  1916.  Heat  seemed  to  toughen  the  fruit  at  first,  but  when 
the  cans  were  opened  a  year  later  this  toughness  was  found  to  have 
disappeared  entirely.  Some  of  the  methods  of  preserving  the  fruit 
are  described  below. 

Plain  Litchi  Sauce. 

3  pounds  fruit  pulp.  2 \  cups  water. 

1  pound  white  sugar 

Boil  the  sugar  and  the  water  together  until  clear.  Add  the  fruit 
pulp  to  this  sirup  and  cook  slowly  without  stirring  for  20  minutes. 
Put  in  sterilized  glass  jars  and  seal.  Wrap  the  jars  in  newspapers 
to  exclude  light.  The  fruit,  when  opened,  is  almost  white  in  color 
with  a  flavor  very  like  fresh  litchi. 


Spiced  Litchi. 


1  pint  water. 

2  pounds  brown  sugar. 

1  ounce  stick  cinnamon. 


2  cloves. 
Litchi  pulp. 


Boil  the  sugar,  water,  and  spices  together  until  the  sugar  melts. 
Add  fruit  pulp  till  the  sirup  barely  covers  it  and  cook  slowly  for  20 
minutes.  Place  in  sterilized  glass  jars  and  seal.  The  fruit  is  flesh 
colored  and  of  a  very  delicate  flavor  when  opened. 


Sweet  Pickled  Litchi. 


1  pint  water. 

2  pounds  brown  sugar. 

1  ounce  stick  cinnamon. 


2  cloves. 

\  cup  vinegar. 

Litchi  pulp. 


15 

Boil  water,  sugar,  vinegar,  and  spices  until  the  sugar  melts.  Add 
to  this  sirup  all  the  fruit  pulp  it  will  cover  and  cook  slowly  20  min- 
utes. Place  in  sterilized  glass  jars  and  seal.  The  fruit,  when 
opened,  is  very  tender,  with  a  raisin  flavor  and  a  whitish  flesh  color. 

DRIED  LITCHI. 

Fruit  pulp,  freed  from  seeds  and  shells,  was  put  on  a  china  plate 
and  dried  in  the  sunlight  for  nine  successive  days.  It  was  very 
sticky  at  first,  then  it  developed  the  texture  and  flavor  peculiar  to  the 
dried  litchi  of  commerce  and  a  reddish-brown  color  about  like  that 
of  raisins.  The  reduced  bulk,  due  to  the  removal  of  the  shells  and 
seeds,  hardly  offset  the  labor  and  the  greater  danger  from  dust  and 
ants  and  other  insects,  while  the  flavor  was  practically  the  same  as 
that  of  the  litchi  nut. 

CANNED  LITCHI. 

A  pint  can  of  litchi  was  bought  in  a  Chinese  store  in  Honolulu, 
which  had  presumably  been  canned  in  China.  The  seeds  and  shells 
had  been  removed  without  marring  the  shape  of  the  fruits,  which 
looked  somewhat  like  big  white  California  cherries  and  had  the  flavor 
of  the  plain  litchi  sauce  canned  at  this  station. 

INSECTS  AND  MITES. 

Several  species  of  insects  and  at  least  one  species  of  mite  cause 
damage  to  the  litchi  tree  or  fruit.  Most  of  these  are  of  minor  im- 
portance, but  they  are  mentioned  here  as  a  matter  of  record  and  in 
order  that  anyone  cultivating  litchis  may  be  on  the  lookout  for 
them. 

It  is  worthy  of  special  notice  that  the  Mediterranean  fruit  fly 
apparently  does  not  breed  in  sound  litchis.  In  the  multitude  of 
observations  made  by  entomologists  no  record  has  been  found  of  the 
litchis  having  been  attacked  by  this  fly  except  where  the  fruit  has 
been  broken  open  by  other  means  and  the  pulp  exposed.  In  this 
respect,  therefore,  the  litchi  may  be  classed  with  the  banana  and 
pineapple  as  practically  immune  to  attacks  of  this  insect  in  its 
normal  state. 

The  litchi  fruit  worm,  the  larva  of  a  tortrieid  moth  (Cryptoplilebia 
''■'If!),  lias  caused  considerable  damage  to  the  fruit  crop  at  times. 
In  its  report  for  1910,  the  entomological  division  of  this  station 
ids  that  in  one  case  practically  the  entire  crop  of  a  private 
orchard  was  destroyed,  but  in  the  following  year,  when  attempts 
were  made  to  prevent  Loss  "by  spraying,  the  moth,  though  apparently 
(loii)'_C  little  damage  to  the  small  litchi  crop,  was  present  as  usual  in 
klu  (Acacia  farnesian  a    and  in  pods  of  koa  (Acacia  Jcoa).     The  moth 


16 

has  been  found  in  litchi  fruit  about  three-fourths  grown,  with  only 
a  slight  brown  point  as  external  evidence  of  the  presence  of  the 
insect.  The  larva  lies  embedded  in  the  flesh,  apparently  not  affecting 
the  seed,  though  it  is  not  certain  that  the  seed  of  infested  fruit  will 
reach  maturity.  As  the  larva  develops  within  the  fruit  the  latter 
splits  open  and  becomes  worthless.  .No  experiments  have  been  comr 
pleted  to  determine  methods  for  the  control  of  this  pest,  but  from 
the  nature  of  the  attack  it  appears  that  arsenicals  probably  would  be 
effective,  arsenate  of  lead  being  perhaps  the  most  promising. 

A  root-inhabiting  mealy  bug,  apparently  a  species  of  Pseudococcus, 
has  been  found  doing  considerable  damage  to  plants  undergoing  the 
process  of  layering.  These  insects  were  found  in  large  numbers  on 
the  callus  formed  where  the  branch  had  been  girdled  to  cause  the 
formation  of  roots.  In  a  number  of  cases  no  roots  were  produced, 
apparently  because  of  the  heavy  demands  of  the  insects  upon  the 
supplies  of  material  at  this  point.  Where  the  presence  of  these 
insects  is  suspected,  the  soil  should  be  removed  from  the  callus  and 
the  insects  destroyed,  either  with  a  solution  of  some  contact  poison, 
as  the  oil  emulsions,  or  a  very  small  amount  of  carbon  bisulphid 
placed  in  the  soil  at  some  distance  from  the  callus.  If  placed  in  the 
soil  an'd  covered,  carbon  bisulphid,  which  is  quite  volatile,  will  pene- 
trate to  all  parts  if  the  soil  is  not  excessively  wet.  If  the  liquid  comes 
in  immediate  contact  with  plant  tissues  it  destroys  them. 

The  hemispherical  scale  (Saissetia  JiemispJterica)  occasionally 
infests  weak  litchi  trees.  This  is  a  waxy,  soft  scale,  brown  to  dark 
brown  in  color,  and  a  well-known  pest  of  several  kinds  of  tropical 
fruit  trees.  Partly  held  in  check  by  natural  enemies,  it  is  not  diffi- 
cult to  control  with  contact  poisons  such  as  the  oil  emulsions. 

The  Japanese  beetle  (Adoretus  tenuimaculatus)  has  been  known  to 
attack  very  young  litchi  trees,  but  it  can  hardly  be  considered  an 
ordinary  pest  of  this  plant.  Vigorous  trees  usually  are  not  infested, 
and  sufficient  protection  during  the  critical  period  is  afforded  by 
arsenical  sprays,  such  as  arsenate  of  lead.  The  natural  enemies  of 
the  beetle  should  also  be  encouraged. 

The  larvae  of  a  moth  (ArcJiips  postvittanus)  occasionally  cause  some 
injury  to  the  foliage  and  the  flowers.  The  habit  of  this  insect  in  its 
attack  upon  the  litchi,  as  well  as  upon  the  avocado  and  several 
other  fruit  trees  and  shrubs,  is  to  sew  together  the  edges  of  the 
leaves  so  as  to  make  a  convenient  hiding  place  from  which  it  can  go 
out  to  feed.  It  may  also  weave  a  web  about  the  flowers  and  destroy 
them.  An  arsenate  of  lead  paste,  containing  15  to  16  per  cent  of 
arsenic  oxid  and  used  in  the  proportion  of  8  pounds  to  100  gallons 
of  water,  will  control  these  larvas  effectively  when  they  appear  in 
any  considerable  numbers. 


Bui.  44,  Hawaii  Agr.  Expt.  Station. 


Plate  V. 


Fig.  1.— Erinose  of  the  Litchi.    Under  Surface  of  Leaf,  Showing  Different 
Stages  in  the  Development  of  the  Disease. 


Fig.  2.— Eriophyes  sp.,  an  Undescribed  Species  of  Mite  Which  Is  the 
Cause  of  the  Erinose  Disease  of  the  Litchi. 

Photomicrograph  by  P.  J.  O'Gara. 


17 

ERINOSE. 

SYMPTOM  S. 

On  February  3,  1916,  attention  was  called  to  a  disease  or  injury  of 
the  litchi  caused  by  mites  which  is  here  designated  as  erinose  because 
of  its  similarity  in  appearance  and  cause  to  the  erinose  of  the  grape 
and  other  plants.  The  tree  most  affected  is  the  oldest  and  has  been 
one  of  the  most  prolific  litchis  in  Hawaii,  while  within  100  feet  of  it 
two  younger  trees  were  found  slightly  affected. 

In  the  early  stages  of  the  malady  small  galls  or  wartlike  swellings, 
often  not  more  than  one-sixteenth  of  an  inch  in  diameter  and  half 
as  high,  appear  upon  the  upper  surface  of  the  leaf  without  producing 
any  discoloration.  On  the  under  surface  may  be  seen  brown  spots, 
which  very  early  begin  to  form  depressions  corresponding  to  the 
swellings  upon  the  upper  surface.  The  galls  increase  in  size  as  the 
trouble  progresses  and  may  become  an  inch  or  more  in  diameter. 
(See  PI.  V,  fig.  1;  PI.  IV,  fig.  2.)  Frequently  the  affected  areas 
become  confluent,  involving  nearly  the  entire  leaflet  and  giving  rise 
to  a  much  crinkled  condition  of  the  upper  and  a  brown  velvety  cov- 
ering on  the  under  surface.  Plate  V,  figure  1,  center,  shows  a  leaf 
in  which  all  the  leaflets  are  involved  and  only  a  few  small  areas 
remain  green.  The  velvety  covering  may  extend  also  to  the  petiole 
or  leaf  stock,  and  in  advanced  stages  it  is  found  even  on  the  young 
twigs. 

A  powerful  hand  lens  shows  that  the  velvety  covering  is  composed 
of  innumerable  trichomes  (plant  hairs),  and  the  trained  eye  occa- 
sionally can  distinguish  the  mites  which  are  the  cause  of  the  trouble, 
though  these  will  escape  the  attention  of  anyone  unfamiliar  with 
them.  With  a  compound  microscope,  magnifying  about  40  diame- 
ters, the  mites  are  plainly  visible  in  vast  numbers  among  the  trichomes. 

Specimens  of  this  mite  have  been  submitted  for  identification  to 
Dr.  L.  O.  Howard,  Chief  of  the  Bureau  of  Entomology,  of  the  Depart- 
ment of  Agriculture,  who  reports  that  the  mite  is  apparently  an 
undescribed  species  of  Eriophyes  (PI.  V,  iig.  2),  the  genus  responsible 
for  similar  diseases  of  other  plants. 

REMEDIES. 

On  February  11,  1916,  three  different  treatments  were  tried.  The 
tree  which  was  most  severely  attacked  was  sprayed  with  a  solution 
of  10  ounces  nicotin  sulphate  and  1|  pounds  whale-oil  soap  in  50 
gallons  of  water.  This  tree,  about  48  feet  in  height  and  48  feet  in 
spread,  received  50  gallons  of  spray  in  the  attempt  to  reach  every 
part.  The  second  tree,  with  a  height  of  20  feet  and  a  spread  of  28 
feet,  was  treated  with  4]   pounds  of  resublinied  flowers  of  sulphur 


18 

in  powdered  form,  applied  with  an  ordinary  powder  bellows.  The 
third  tree,  with  a  height  of  24  feet  and  a  spread  of  30  feet,  was  sprayed 
with  self-boiled  lime-sulphur  solution  made  up  of  4  pounds  quick- 
lime and  4  pounds  flowers  of  sulphur  in  25  gallons  of  water,  to  which 
2  pounds  of  arsenate  of  lead  was  added  to  kill  an  occasional  larva 
of  At chips  postvittanus. 

Fresh  material  from  the  treated  trees  was  gathered  and  examined 
on  February  19.  That  from  the  first  tree  sprayed  with  nicotin  sul- 
phate and  fish-oil  soap,  revealed  only  10  living  Eriophyes  after  a  search 
for  a  half  hour  with  a  microscope.  On  the  second  tree,  which  had  been 
treated  with  flowers  of  sulphur  in  powdered  form,  many  dead  but  also 
many  living  mites  were  found.  The  material  from  the  third  tree,  which 
had  been  sprayed  with  self -boiled  lime-sulphur,  showed  few  Eriophyes 
where  the  spray  had  settled,  but  in  places  that  had  escaped  many 
were  living. 

The  treatment  was  repeated  on  February  26,  1916.  Later  exami- 
nation disclosed  results  so  much  more  favorable  to  the  nicotin  sul- 
phate and  fish-oil  soap  that  the  other  treatments  were  abandoned. 
This  spray  was  applied  again  on  March  28,  and  April  11  and  25.  One 
tree  received  treatment  on  March  11.  By  the  end  of  April  the  mites 
were  practically  eradicated. 

IMMUNITY   OF   THE    LONGAN. 

A  longan  tree,  situated  about  midway  between  two  of  the  diseased 
litchi  trees  referred  to  above  and  less  than  50  feet  from  either,  has 
presented  no  indication  of  erinose,  and  a  search  of  the  leaves  has 
revealed  no  Eriophyes,  although  certain  other  mites  are  present,  pro- 
ducing a  yellowish-powdery  effect,  not  uncommon  on  mite-infested 
plants. 

VARIETIES. 

There  are  many  varieties  of  litchi,  propagated  by  the  air-layering 
or  "gootee"  method  referred  to  above  and  cultivated  under  varietal 
names.  The  origin  of  most  of  these  varieties  is  unknown  in  this 
country,  and,  indeed,  the  origin  of  some  of  them  is  so  ancient  that  it 
is  doubtful  whether  the  most  careful  research  in  the  lands  to  which 
they  are  indigenous  would  reveal  anything  of  value  concerning 
them.  It  is  probable  that  most  kinds  have  originated  as  chance 
seedlings,  although  some  may  have  arisen  as  bud  mutations.  Fruits 
of  established  identity  are  not  available  for  the  making  of  accurate 
pomological  descriptions  of  any  of  the  varieties,  and  no  full  de- 
scriptions have  been  found.  The  following  fist  of  choice  varieties  in 
China,  with  valuable  notes  concerning  each,  has  been  taken  from  a 
report  by  United  States  Consul  F.  D.  Cheshire:1 

i  U.  S.  Dept.  Agr.,  Bur.  Plant  Indus.,  Plant  Immigrants  No.  111-112  (1915),  pp.  918,  919. 


19 

1.  Yuk-ho-po— "jade  purse  "—having  a  thick  skin,  green  color,  a  large  kernel, 
and  a  sour  taste.  It  is  inferior  in  quality,  but  ae  it  is  the  first  to  make  its  appearance, 
coming  in  about  the  5th  of  May,  it  is  given  a  good  reception. 

2.  Hark-yip— "black  leaf"— dark  red  in  color,  delicate  skinned,  fragrant,  and 
sweet.  This  is  one  of  the  best  lichees  and  comes  into  bearing  about  June  6.  The  best 
of  this  variety  is  produced  in  the  Tung  Kun  district  and  the  Shui  Tung  district.  It 
is  plentiful  in  the  market  and  very  popular. 

3.  Kat-jat-kwo — '"coackroach  fruit" — dark  red,  thick  skinned,  pear  shaped.  This 
fruit  is  inferior  in  quality. 

4.  Wai-chi — "wai  fruit" — the  most  common  variety  of  lichees  on  the  market  in 
Kwangtung  Province.  Some  are  light  and  some  are  dark  red  in  color,  and  are  thin 
skinned.  It  is  produced  between  the  21st  of  May  and  the  21st  of  June  and  is  con- 
sidered a  good  variety. 

5.  Chui-ma-chi — "green-spotted  lichee" — of  a  green  color  and  sour  taste.  There 
are  very  few  in  the  market. 

6.  Tong-pok — "sugar  sheets" — of  a  dark  red  color,  pear  shaped,  and  sweet  flavor, 
but  not  of  a  delicious  taste.  It  is  produced  for  the  most  part  in  the  Namhoi  and 
Samshui  districts. 

7.  Kicai-mi — "cinnamon  flavor" — light  red,  rough  skinned,  small  kernel,  very 
fragrant  and  sweet.  One  of  the  best  varieties  of  lichees.  It  is  placed  on  the  market 
about  June  21.     The  best  are  obtained  from  Lo  Kong  Tung,  in  the  Pun  Yu  district. 

8.  Shan-chi — "hill  fruit" — of  a  red  color  and  round  shape,  slightly  sour. 

9.  Hom-shiu-chi — "magnolia  fruit" — light  red,  small  sized,  sweet  tasting,  but  not 
delicious.     Attached  to  each  lichee  of  this  species  is  a  smaller  green  one. 

10.  No-mai-chi — "glutinous  rice  cake."  This  is  one  of  the  most  popular  lichees, 
thin  skinned,  fragrant  and  sweet,  and  good  appearance.  It  has  a  very  small  kernel 
and  a  heavy  pulp.  It  is  produced  in  the  month  of  June  and  comes  mostly  from  Pun 
Yu  and  Canton. 

11.  Fei-tsze-siu — "smiling  imperial  concubine  " — half  red,  half  green,  round  shaped, 
thick  rough  skin;  good  flavor,  with  a  slightly  sour  taste.  It  is  produced  at  the  end 
of  June,  mostly  in  Shiu  Kwan  and  Ying  Tak,  and  is  considered  a  good  fruit. 

12.  Chun  Fung — "phoenix  lichee" — small,  round,  of  a  red  color  and  thick  skin; 
not  good  in  taste. 

13.  Heung-lai — "fragrant  lichee" — produced  in  the  Sun  Hing  district;  small  and 
round,  of  a  red  color  and  rough  skinned;  fragrant  and  sweet.  It  was  formerly  an 
article  of  tribute  to  the  throne.     The  heung-lai  is  produced  at  the  end  of  June. 

14.  Kica-luk — "green  mounted  lichee."  This  lichee  is  grown  in  the  Tsang  Shing 
district.  Its  characteristics  are  a  round  shape,  fine  skin,  and  delightful  red  color; 
fragrant  and  sweet.  It  is  considered  superior  to  the  no-mai-chi  and  the  best  lichee 
that  can  be  had  in  Kwangtung  Province.  It  is  difficult  to  obtain  in  the  market. 
This  species  usually  grows  in  pairs — one  large  red,  and  the  other  a  small  green.  The 
green  one  is  not  edible.  The  genuine  kwa-luk  is  grown  from  only  one  tree,  which  is 
inside  the  Tsang  Shing  magistracy.  During  the  Manchu  regime  the  fruit  of  this  tree 
was  accepted  as  tribute  by  the  Emperor.  The  lichees  of  this  variety  grown  in  the 
neighborhood  are  also  considered  as  good  fruit,  but  they  are  almost  monopolized  by  the 
officials.  The  bun-Ink  lichee  is  chiefly  used  for  presentation  purposes  between 
officials,  from  two  to  eight  lichees  being  placed  in  one  box.  The  genuine  kwa-luk  can 
be  obtained  only  with  great  difficulty. 

15.  Sheung-shu-iiai — "Chancellor's  wai-chi" — produced  in  the  Tsang  Shing  district. 
•  mbles  the  wai-chi  in  appearanpe,  but  its  taste  is  that  of  the  no-mai-chi.     It  is 

one  of  the  best  varieties  of  the  lichees  and  is  placed  on  the  market  about  the  7th  of 
July. 


20 

In  India  several  varieties  are  very  highly  esteemed.  A  variety 
known  as  " McLean"  is  said  to  be  one  of  the  best  in  that  country. 
Another  under  the  name  "Muzaffarpur  Seedless,"  is  practically  seed- 
less in  many  of  its  fruits.  "Bedana"  is  another  small-seeded,  sweet 
variety.  "Dudhia"  is  quite  unusual  in  that  it  is  white.  "Rose 
Scented"  is  a  fruit  of  large  size  and  very  agreeable  flavor.  "China" 
is  a  late-season  variety. 

BOTANICAL  STATUS  AND   RELATIONSHIPS. 

Closely  related  to  the  litchi  is  the  longan  or  loongyan,  Euphoria 
longana  or  Dimocarpus  longan.  This,  which  has  been  mentioned 
above,1  is  a  tree .  attaining  a  height  of  40  to  50  feet  and  producing 
abundant  straw-yellow  fruits  about  three-quarters  of  an  inch  in 
diameter.  The  fruits,  sometimes  called  dragon's  eyes,  are  borne  in 
terminal  or  axillary  clusters  and  have  a  shell-like  covering  similar 
to  that  of  the  litchi  and  a  fleshy  aril  surrounding  the  seed  but  free 
from  it.  In  texture  it  is  quite  similar  to  the  litchi,  but  in  flavor  it  is 
not  equal  to  that  fruit.  The  longan  is  indigenous  to  British  India. 
De  Candolle  states  that  it  is  wild  "from  Ceylon  and  Concan  as  far  as 
the  mountains  to  the 'east  of  Bengal,  and  in  Pegu."  2  It  was  early 
introduced  into  the  Malay  Archipelago  and  China,  where  it  is  now 
extensively  cultivated  for  its  fruits.  The  statement  has  been  made 
that  it  is  of  slower  growth  than  the  litchi,  but  this  certainly  does  not 
hold  true  under  Hawaiian  conditions,  where  it  is  a  robust  tree  far 
exceeding  the  litchi  in  vigor  and  rapidity  of  growth.  As  in  the  case 
of  the  litchi,  seedlings  frequently  are  very  tardy  in  coming  into 
bearing. 

Another  closely  related  species  is  the  rambutan  (Nephelium  lappa- 
ceum),  believed  to  be  a  native  of  the  Indian  Archipelago  and  now 
cultivated  very  generally  about  Singapore  and  the  Straits  Settle- 
ments. The  fruits  are  borne  in  clusters  and  are  considerably  larger 
than  those  of  the  litchi,  with  a  leathery  pericarp  and  soft  fleshy 
spines.  The  rambutan  apparently  never  has  been  introduced  into 
Hawaii,  probably  because  of  the  short  life  of  the  seeds  and  the  diffi- 
culty of  transporting  the  young  trees.  It  is  believed  the  careful  and 
painstaking  effort  which  would  be  required  in  introducing  the  ram- 
butan and  in  testing  its  adaptibility  would  be  fully  repaid. 

Still  another  of  the  relatives  of  the  litchi  is  the  pulassan  (Nephelium 
mutabile),  which  closely  resembles  the  rambutan  but  is  said  to  be 
even  more  highly  prized  in  its  native  country. 

Until  recently  all  the  species  mentioned  above  have  been  placed 
in  the  genus  Nephelium,  the  litchi  being  designated  Nephelium  litchi; 
the  longan,  N.  longana;  the  rambutan,  N.  lappaceum;  and  the  pulas- 

i  Vide,  p.  11.  2  Origin  of  Cultivated  Plants,  London,  1884,  p.  315. 


21 

san,  N.  mutabile.  Recent  botanists,  however,  separate  them  into 
the  genera  Litchi,  Euphoria  or  Dimocarpus,  and  Nep helium,  as  indi- 
cated above.  The  characters  upon  which  this  separation  is  based 
are  recorded  as  follows : * 

Euphoria.  Fruit  tubercled  with  rugose,  flattened,  sometimes  indistinct  tubercles; 
aril  free;  embryo  straight,  radicle  at  the  base  of  the  seed;  petals  present;  sepals 
imbricate:  Includes  the  longan  or  longyen  (E.  longana,  Lam.  Ncphelium  lon<j<nm, 
Cambess.  See  Euphoria).  Litchi.  Fruit  tubercled  with  angular  prominent  tuber- 
dee;  aril  free,  embryo  straight,  radicle  at  the  base  of  the  seed;  petals  wanting;  sepals 
valvate,  small:  Includes  the  litchi  (Litchi  chinensis,  Sonn.  Ncphelium  litchi,  Cambess. 
See  Litchi).  Nephelium.  Fruit  echinate-muricate,  sometimes  smooth;  aril  adnate 
to  the  seed;  embryo  curved,  the  radicle  near  the  apex  of  the  seed;  petals  wanting,  in 
some  species  present;  sepals  valvate,  small. 

The  three  species  mentioned  above  may  be  distinguished  by  the  leaves  as  follows: 
The  longan  has  usually  four  pairs  (2  to  5)  of  leaflets,  coriaceous,  strongly  veined, 
acuminate  but  more  or  less  obtuse  at  point,  2  to  4  inches  or  more  long;  the  litchi  has 
usually  three  pairs  of  leaflets,  coriaceous,  indistinctly  veined,  glaucous  beneath, 
obtusely  acuminate,  2  to  5  inches  long;  the  rambutan  has  usually  two  to  three  or  more 
pairs  of  leaflets,  chartaceous,  strongly  veined,  often  obtuse,  3£  to  7  inches  long;  the 
midrib  is  somewhat  raised  above,  impressed  in  the  two  preceding  species. 

Other  related  species  of  Sapindacese  might  be  mentioned,  but  only 
those  have  been  included  which  are  rather  common  in  the  Orient  and 
which  are  so  closely  related  to  the  litchi  as  formerly  to  have  been 
placed  in  the  same  genus.  There  is  a  considerable  number  of  species 
suitable  for  the  experimental  use  of  plant  propagators  and  for  the 
work  of  plant  breeders. 

ACKNOWLEDGMENTS. 

It  is  desired  to  express  appreciation  here  of  the  kind  assistance 
rendered  by  several  gentlemen  who  have  long  cultivated  the  litchi 
in  Hawaii,  including  Messrs.  Ching  Shai,  C.  K.  Ai;  Wong  Leong,  and 
others.  Much  valuable  information  concerning  the  litchi  in  foreign 
countries  has  been  received  through  correspondence  with  many  bota- 
nists and  horticulturists,  among  whom  should  be  mentioned  especially 
Messrs.  G.  Weidman  Groff,  of  Canton  Christian  College,  China;  A.  C. 
Hartless,  superintendent,  Government  Botanical  Gardens,  Saharan- 
pur,  India;  G.  T.  Lane,  curator,  Royal  Botanic  Garden,  Calcutta; 
and  G.  S.  Varma,  garden  overseer,  Lahore,  India.  To  all  of  these 
and  others  this  opportunity  is  taken  to  express  thanks. 

1  Bailey,  L.  U.    Standard  Cyclopedia  of  Horticulture,  New  York,  1910,  vol.  4,  p.  2131. 


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